Seismic data is gathered and analyzed for many different purposes. For example, seismic data is used to identify fault zones for earthquake predictions, plan and mine for minerals, and extract fluids, such as hydrocarbons, and drilling other wells from the Earth's subsurface formations.
For example, with respect to extracting fluids, seismic data is used in a variety of stages of the process. Specifically, obtaining fluids generally require a planning stage, a drilling stage, and a production stage. Each stage may be performed one or more times. In the planning stage, surveys are often performed using acquisition methodologies, such as seismic mapping to generate acoustic images of underground formations. The seismic data is analyzed to determine the presence of subterranean assets, such as valuable fluids or minerals, or to determine whether the formations have characteristics suitable for storing fluids. Although the subterranean assets are not limited to hydrocarbons such as oil, throughout this document, the terms “oilfield” and “oilfield operation” may be used interchangeably with the terms “field” and “field operation” to refer to a site where any types of valuable fluids or minerals can be found and the activities required to extract them. The terms may also refer to sites where substances are deposited or stored by injecting substances into the surface using boreholes and the operations associated with this process.
During the drilling stage, a borehole is drilled into the earth at a position identified during the survey stage. Specifically, a drilling rig rotates a drill string that has a bit attached. Casing may be added to ensure the structural integrity of the borehole. During drilling, seismic data is used to direct the trajectory, or path in which the borehole is drilled.
During the completion stage, the drilling equipment is removed and the well is prepared for production. During the production stage, fluids are produced or removed from the subsurface formation. In other words, the fluids may be transferred from the subsurface formation to one or more production facilities (e.g. refineries). During the completion stage and production stage, seismic data may be used to analyze and monitor the processes of the respective stages.